Sewing machine thread supply spool friction brake

ABSTRACT

A thread spool supporting spindle assembly for mounting on the conventional spool pin atop a sewing machine. The spindle assembly includes structure by which a light friction drag is applied to the spool of thread supported from the spool pin and thereby prevents inertia of the supported spool of thread tending to cause the thread spool to coast ahead when operation of the associated sewing machine is terminated after operating at high speed, such overrunning of the thread spool causing excessive slack in the thread which can subsequently result in thread breakage when the sewing machine is again started at high speed. The spindle assembly of the instant invention may be utilized on any sewing machine which includes a vertical, or substantially vertical, spool pin located atop the sewing machine and includes felt disk structure for initial downward displacement over the spool pin with the diameter of the center opening in the felt disk structure being smaller than the diameter of the pin thereby affording a friction fit between the felt disk structure and the pin so that a thread spool disposed over the pin above the felt disk will drop by gravity into engagement with the felt disk assembly to thus frictionally resist overrunning of the thread spool.

States Patent 1 1 McCallister SEWING MACHINE THREAD SUPPLY SPOOLFRICTION BRAKE [76] Inventor: Dennis L. McCallister, 331 Hall St.,

Wayne, W. Va. 25570 [22] Filed: Apr. 20, 1972 [21] Appl. No.: 245,846

[52] 11.5. C1. 223/106, 242/156 [51] Int. Cl A4111| 31/00 [58] Field ofSearch 112/218 R, 254, 255;

Primary Examiner-Jordan Franklin Assistant Examiner-Peter NerbunAttorney-Harvey B. Jacobson [57] ABSTRACT A thread spool supportingspindle assembly for mounting on the conventional spool pin atop asewing machine. The spindle assembly includes structure by which a lightfriction drag is applied to the spool of thread supported from the spoolpin and thereby prevents inertia of the supported spool of threadtending to cause the thread spool to coast ahead when operation of theassociated sewing machine is terminated after operating at high speed,such overrunning of the thread spool causing excessive :slack in thethread which can subsequently result in thread breakage when the sewingmachine is again started at high speed. The spindle assembly of theinstant invention may be utilized on any sewing machine which includes avertical, or substantially vertical, spool pin located atop the sew ingmachine and includes felt disk structure for initial downwarddisplacement over the spool pin with the diameter of the center openingin the felt disk structure being smaller than the diameter of the pinthereby affording a friction fit between thefelt disk structure and thepin so that a thread spool disposed over the pin above the felt diskwill drop by gravity into engagement with the felt disk assembly to thusfrictionally resist overrunning of the thread spool.

7 Claims, 3 Drawing Figures PATENTED 1973 3. 762.615

Fig. 2

SEWING MACHINE THREAD SUPPLY SPOOL FRICTION BRAKE The main object ofthis invention is to provide an attachment for a conventional sewingmachine which may be readily added to the sewing machine and utilized toprevent excessive overrunning of an associated thread spool.

Another object of this invention, in accordance with the immediatelypreceding object, is to provide a thread spool spindle constructionwhich may be readily applied, in a removable manner, to substantiallyall sewing machines provided with vertically disposed spool pins thereatop.

A final object of this invention to be specifically enumerated herein isto provide a device in accordance with the preceding objects and whichwill conform to conventional forms of manufacture, be of simpleconstruction and automatic in operation so as to provide a device thatwill be economically feasible, long lasting and relatively trouble free.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout.

FIG. 1 is a fragmentary perspective view of a conventional form ofsewing machine with the thread spool spindle assembly of the instantinvention operatively associated with the spool pin of the sewingmachine and a spool of thread mounted on the spindle assembly;

FIG. 2 is an exploded perspective view of the spindle assembly of theinstant invention; and

FIG. 3 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by the section line 3--3 of FIG.1.

Referring now more specifically to the drawings, the numeral generallydesignates a conventional form of sewing machine including an upperhorizontal portion 12 upwardly from which a vertical spool pin 14projects. Conventionally, a spool 16 of thread 18 is loosely telescopedover and rotatably disposed on the spool pin 14 in a manner such thatthe spool 16 is free to rotate relative to the pin 14 as the thread 18is pulled from the spool 16 through the guides 20 and 22 of the sewingmachine 10.

When the machine 10 is operating at high speed the thread l8is unwoundfrom the spool pin 14 in a relatively rapid manner so that when themachine 10 is suddenly stopped the spool 16 tends to rotate in thethread unwinding direction and thereby unwinds sufficient thread 18 fromthe spool 16 after operation of the ma chine 10 has been terminated tocause excessive slack in the thread l8extending from the spool 16. Then,when the machine 10 is suddenly again placed in operation at high speed,the thread 18 is suddenly tensioned and there is a tendency for thethread to be broken.

The spool spindle assembly of the instant invention is referred to ingeneral by the reference numeral 24 and includes a thin walled sleeve 26which may be telescoped over the pin 14, a pair of vertically spacedfelt disks 28 and 30, a pair of felt wedges 32 and 34 for dispositionbetween corresponding diametrically opposite portions of the disks 28and and a plastic strap 36 having an aperture 38 formed in one end and apair of metal weights 40 secured to the apertured end of the strap 36 onopposite sides of the aperture 38.

With attention invited to FIGS. 2 and 3 of the drawings it may be seenthat the disks are disposed in vertically spaced relation with thewedges 32 and 34 disposed between corresponding pairs of diametricallyopposite portions of the disks 28 and 30. The disks 28 and 30 as well asthe wedges 32 and 34' are secured together in any convenient manner suchas by a glue or adhesive (not shown) and the disk assembly or overallstructure comprising the disks 28 and 30 and the wedges 32 and 34 areslipped downwardly over the spool pin 14. The disks 28 and 30 areprovided with center apertures 42 and 44 which are at least slightlysmaller in diameter than the diameter of the spool pin 14 and thus thedisks 28 and 30 have to be forced dlownwardly over the upper rounded endof the pin 14 and the disks 28 and 30 are frictionally engaged with thepin 14 to thus retard rotation of the disk assembly relative to the pin14. The end of the plastic strap 36 remote from the aperture 38 issecured between the disks 28 and 30 and between the wedges 32 and 34 inany convenient manner such as by an adhesive or glue (not shown) and theaperture 38 in the weighted end of the strap 36 is of a diameter largerthan the diameter of the sleeve 26.

After the disk structure comprising the disks 28 and 30 and the wedges32 and 34 has been passed downwardly over the spool pin 14, the sleeve26 is telescoped downwardly over the pin 1.4 and is rotatable relativeto the latter. The lower end of the sleeve 26 abuts against the upperside of the disk 30 and the spool 16 is thereafter downwardly telescopedover the sleeve 26 and the weighted end of the strap 36 is passed overthe upper end of the sleeve 14 so that the weighted end of the strap 36may engage the upper end of the spool 16 while the lower end of thespool 16 rests upon the diametrically opposite portions of the upperdisk 30 beneath which the wedges 32 and 34 are disposed.

The apertured end of the plastic strap 36 is disposed in frictionalengagement with the upper end of the spool 16 and the lower end of thespool 16 is frictionally engaged with the diametrically oppositeportions of the disk 30 having the wedges 32 and 34 disposed thereunder.Accordingly, this frictional engagement of the strap 36 and the disk 30with the spool 16 tends to retard rotation of the spool and thus toprevent contin-. ued rotation of the spool in a thread unwindingdirection when the operation of the sewing machine issuddenly terminatedfrom high speed operation. In this manner, the formation of slack in thethread 18 extending from the spool 16 is eliminated and the sewingmachine 10 may be again immediately oerated at high speed without thedanger of breaking the thread 18.

Inasmuch as the spool pins of substantially all types of sewing machinesare of generally the same size the spool assembly 24 of the instantinvention may'be utilized on substantially all sewing machines providedwith vertical spool pins mounted there atop. Further, the spindleattachment or assembly 24 requires no modifications to be made in theassociated sewing machine 10 and the assembly 24 may be readilyconstructed in an inexpensive manner.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. In combination with a sewing machine portion including a generallyvertical spool pin projecting upwardly from an upper portion thereof, aspool rotation retarding attachment, said attachment comprising frictiondisk means telescoped downwardly over said pin and frictionally engagedwith the latter to resist rotation of said disk means relative to saidpin, said disk means including upper surface means adapted forfrictional engagement with the lower end surface of a thread spooltelescoped downwardly over said pin above said friction disk means, astrap including a first weighted and apertured end engaged over theupper end of said pin after a spool of thread has been telescopeddownwardly over said pin on top of said disk means, the other end ofsaid strap being anchored to said disk means and preventing a fullrevolution of said first end about said pin relative to said disk means,said weighted end being loosely slidable on said pin whereby theweighted end may rest, by gravity, in frictional engagement with theupper end of a spool of thread disposed on said pin.

2. The combination of claim 1 wherein said friction disk means includesupper and lower disks constructed of deformable and somewhat resilientmaterial, spacing members disposed between diametrically oppositeportions of said disks, said upper disk being at least somewhat flexiblewhereby the central portion of the upper disk may be displaceddownwardly relative to the diametrically opposite portions thereof belowwhich said spacing members are disposed.

3. The combination of claim 1 wherein said disks are constructed of feltmaterial.

4. The combination of claim 1 wherein said disk means includes upper andlower portions thereof constructed of felt, said disk means having anopening formed centrally therethrough of a smaller diameter than saidpin, said pin being forced through said opening with the lattersufficiently enlarged to be received over said pin with said disk meansin frictional engagement with said pin.

5. The combination of claim ll wherein said friction disk means includesupper and lower disks constructed of deformable and somewhat resilientmaterial, spacing members disposed between diametrically oppositeportions of said disks, said upper disk being at least somewhat flexiblewhereby the central portion of the upper disk may be displaceddownwardly relative to the diametrically opposite portions thereof belowwhich said spacing members are disposed.

6. For use in conjunction with an upright spool pin of a sewing machine,a friction disk attachment for retarding rotation ofa spool or thread tobe mounted on said spool pin, said attachment comprising disk meanshaving a central opening formed therethrough of a size to receive saidpin therethrough with the latter frictionally engaged with portions ofsaid disk means defining said opening, one side of said disk meanscomprising an upper side and defining friction surface means forfrictionally engaging the lower end of a thread spool telescoped oversaid pin above said disk means, a strap including a first weighted andapertured end engaged over the upper end of said pin after a spool ofthread has been telescoped downwardly over said pin on top of said diskmeans, the other end of said strap being anchored to said disc means andpreventing a full revolution of said first end about said pin relativeto said disk means, said weighted end being loosely slidable on said pinwhereby the weighted end may rest, by gravity, in frictional engagementwith the upper end of a spool of thread disposed on said pin.

7. In combination with a sewing machine portion including a generallyvertical spool pin projecting upwardly from an upper portion thereof, aspool rotation retarding attachment, said attachment comprising frictiondisk means telescoped downwardly over said pin and frictionally engagedwith the latter to resist rotation of said disk means relative to saidpin, said disk means including upper surface means adapted forfrictional engagement with the lower end surface of a thread spooltelescoped downwardly over said pin above said friction disk means, anda weighted apertured body portion loosely engaged over the upper end ofsaid pin after a spool of thread has been telescoped downwardly oversaid pin on top of said disk means, said body portion being freelyslidable on said pin for resting upon, by gravity, and frictionalengagement with the upper end of said spool, and means connecting saidbody portion to said disk means preventing a full revolution of saidbody portion about said pin relative to said disk means.

1. In combination with a sewing machine portion including a generallyvertical spool pin projecting upwardly from an upper portion thereof, aspool rotation retarding attachment, said attachment comprising frictiondisk means telescoped downwardly over said pin and frictionally engagedwith the latter to resist rotation of said disk means relative to saidpin, said disk means including upper surface means adapted forfrictional engagement with the lower end surface of a thread spooltelescoped downwardly over said pin above said friction disk means, astrap including a first weighted and apertured end engaged over theupper end of said pin after a spool of thread has been telescopeddownwardly over said pin on top of said disk means, the other end ofsaid strap being anchored to said disk means and preventing a fullrevolution of said first end about said pin relative to said disk means,said weighted end being loosely slidable on said pin whereby theweighted end may rest, by gravity, in frictional engagement with theupper end of a spool of thread disposed on said pin.
 2. The combinationof claim 1 wherein said friction disk means includes upper and lowerdisks constructed of deformable and somewhat resilient material, spacingmembers disposed between diametrically opposite portions of said disks,said upper disk being at least somewhat flexible whereby the centralportion of the upper disk may be displaced downwardly relative to thediametrically opposite portions thereof below which said spacing membersare disposed.
 3. The combination of claim 1 wherein said disks areconstructed of felt material.
 4. The combination of claim 1 wherein saiddisk means includes upper and lower portions thereof constructed offelt, said disk means having an opening formed centrally therethrough ofa smaller diameter than said pin, said pin being forced through saidopening with the latter sufficiently enlarged to be received over saidpin with said disk means in frictional engagement with said pin.
 5. Thecombination of claim 1 wherein said friction disk means includes upperand lower disks constructed of deformable and somewhat resilientmaterial, spacing members disposed between diametrically oppositeportions of said disks, said upper disk being at least somewhat flexiblewhereby the central portion of the upper disk may be displaceddownwardly relative to the diametrically opposite portions thereof belowwhich said spacing members are disposed.
 6. For use in conjunction withan upright spool pin of a sewing machine, a friction disk attachment forretarding rotation of a spool or thread to be mounted on said spool pin,said attachment comprising disk means having a central opening formedtherethrough of a size to receive said pin therethrough with the latterfrictionally engaged with portions of said disk means defining saidopening, one side of said disk means comprising an upper side anddefining friction surface means for frictionally engaging the lower endof a thread spool telescoped over said pin above said disk means, astrap including a first weighted and apertured end engaged over theupper end of said pin after a spool of thread has been telescopeddownwardly over said pin on top of said disk means, the other end ofsaid strap being anchored to said disc means and preventing a fullrevolution of said first end about said pin relative to said disk means,said weighted end being loosely slidable on said pin whereby theweighted end may rest, by gravity, in frictional engagement with theupper end of a spool of thread disposed on said pin.
 7. In combinationwith a sewing machine portion including a generally vertical spool pinprojecting upwardly from an upper portion thereof, a spool rotationretarding attachment, said attachment comprising friction disk meanstelescoped downwardly over said pin and frictionally engaged with thelatter to resist rotation of said disk means relative to said pin, saiddisk means including upper surface means adapted for frictionalengagement with the lower end surface of a thread spool telescopeddownwardly over said pin above said friction disk means, and a weightedapertured body portion loosely engaged over the upper end of said pinafter a spool of thread has been telescoped downwardly over said pin ontop of said disk means, said body portion being freely slidable on saidpin for resting upon, by gravity, and frictional engagement with theupper end of said spool, and means connecting said body portion to saiddisk means preventing a full revolution of said body portion about saidpin relative to said disk means.